Dynamics of alpine ranges and areas utilized by introduced ... · Dynamics of alpine ranges and...
Transcript of Dynamics of alpine ranges and areas utilized by introduced ... · Dynamics of alpine ranges and...
Dynamics of alpine ranges and areas utilized by introduced caribou
populations on the Kenai Peninsula, Alaska1
ABSTRACT
Alpine vegetation in the Kenai Peninsula, southcentral Alaska, was studied in relation to
the winter grazing of introduced caribou populations. Vegetation structure differed more from
area to area than did the measured environmental variables. Thus, biotic differences (including
presence of caribou) may play a more important role in vegetation variation than does the
physical environment. Lichens varied more from area to area than did vascular plants. Increased
caribou density is associated with a decrease in preferred lichen species and increasing
dominance of vascular plants. These results were also compared in a 10-year trends study
involving a portion of these ranges.
Keywords: Caribou introduction, lichens, 10-year trends study, cover, macroplot, dominance.
INTRODUCTION
The Kenai Peninsula in southcentral Alaska (Fig.1) historically supported a population of
caribou (Porter, 1893; SetonKarr, 1887; Schiefner, 1874; and Palmer, 1938); by the early 1900’s
caribou populations were eliminated from the peninsula (Palmer 1938). This extirpation has been
attributed to both habitat change and human overharvest. Davis and Franzmann (1979) believes
the latter is a “more proximate cause of extermination” than the former. To restore caribou
populations on the peninsula, cooperative efforts between the Kenai National Wildlife Refuge
(KNWR) and the Alaska Department of Fish and Game (ADF&G) have made several
introductions on the peninsula. In 1965-1966 caribou (Rangifer tarandus granti) from the
Nelchina herd, in southcentral Alaska, were introduced on the peninsula (Burns & McKnight,
1973). This population occupied the northern portions of the peninsula. During the month of
April in 1985 and 1986, caribou from the same herd were captured and released on the southern
portions of the Kenai Peninsula (Bailey, 1985; Bailey, et. al. 1990). These relocation efforts
have currently resulted in the establishment of four herds, the Killey River, Fox River, Kenai
Mountains, and Kenai Lowland Herds. There were five different herds at one time (i.e., Twin
Lakes Herd), but currently there are four as this herd combined with the Killey River Herd. The
1 State of Alaska ([email protected])
1
Kenai Mountains population is increasing while the other three herds have all declined over the
past 5-8 years. The details concerning the methods utilized for the caribou introductions,
monitoring and spatial analysis, and population viability information is presented in Ernst, et. al.
2007 (in-prep).
Two environmental needs of caribou stand out above all others: 1) to escape or find relief
from flying insects in the summer; and 2) to find food through deep snow in the winter
(Bergerud, 1978). The winter survival of many caribou and reindeer populations living in sub-
arctic or northern taiga areas depends on the availability of their preferred lichen food (mostly
Cladina spp.) (Palmer & Rouse, 1945; Andreev, 1954; Pegau, 1968; Helle & Aspi, 1983). The
slow rate of lichen growth is widely recognized. It has been standard practice to keep animal
density at a level corresponding to the carrying capacity of the winter range. The winter range
has typically been considered as the more limiting forage resource due to snow and other
environmental variables that may reduce its availability. They are highly adapted to their
environment and highly adaptable (Bergerud, 1978). The only other large mammal that may
exhibit some interspecific competition for the caribou range resources is the Dall Sheep (Ovis
dalli). Although, it has been recognized that the dominance of Dall’s sheep diet in Alaska is
prefer graminoids (66%) compared to other flora (Nichols Unpublished, in Schmidt and Gilbert,
1978) while the caribou specialize in lichens.
This study documents the vegetation composition, with special emphasis on lichens, of
the winter ranges (December through March) utilized by the Killey River, Fox River, Kenai
Mountains introduced caribou populations, and differences between these ranges with
comparable areas without caribou presence. It provides an initial assessment of the condition of
these ranges (1988 & 1989), as well as a 10-year revisit (1998) to a portion of these ranges. This
information provides both baseline and trend information for the maintenance and management
of these vegetation communities as a sustainable caribou forage resource. From it, some
generalizations are made about the influence of both herbivores and the environmental factors
(i.e., wind, elevation, aspect, etc.) on the structure of vegetation. Nomenclature for lichens
follows Egan (1987) and for vascular plants follow Hultén (1968).
2
STUDY AREA
The Kenai Peninsula (26,000 km2), hereafter referred to as the Peninsula, in southcentral
Alaska is located in the sub-arctic zone (59°05’- 61°05’ N., and 152°00’- 148°00’ W.) flanked
by Prince William Sound to the east, the Cook Inlet to the north and west, and the Pacific Ocean
to the south (Fig. 1). The peninsula encompasses a total area of 26,000 km2, with a 16-km
connection to the mainland. This area is characterized as within the Cook Inlet Basin and
Chugach-St. Elias Mountains Ecoregions (Nowacki, et. al. 2001). The narrow isthmus creates
insular conditions from many of the biological resources on the Peninsula (Fig. 2). Climate is
typically intermediate between the drier, continental type of the Alaskan interior and the wetter,
mild maritime climate of southern, coastal areas (Karlstrom 1964). Major topographic features
include the Kenai Mountains to the south and east, which rise to 1,600 m., the extensive Harding
Icefield (approx 1,800 km2) with associated glaciers, the Skilak-Tustumena benchlands
averaging roughly 925 m. elevation, and the forested northern and western lowlands (<150 m.).
The alpine tundra vegetation community, where the caribou populations of this study
winter, consists of short-stemmed perennial herbs, low growing or prostrate shrubs, lichens and
mosses. Common in these areas are low mats of Dryas octopetala, Empetrum nigrum, and
Oxytropis nigrescens. Much of the landscape consists of barren rock and rubble with scattered
plants. The alpine tundra has low primary productivity, low decomposition rates, short growing
seasons, and high susceptibility to physical disturbance (Miller, 1982; Klein & Lent, 1988).
Lichen communities on alpine ranges change quickly with disturbance (e.g., trampling and
grazing), and the time required for recovery is directly proportional to the degree of disturbance
(Helle & Aspi, 1983; Pegau, 1975; Miller, 1982). The recovery of the lichen community is
further complicated by competition with the vascular-plant community (Swanson & Barker,
1992). These processes are dynamic, and may express continued changes based on both the
biotic influences, such as herbivory pressure or interspecific competition, and abiotic influences.
In reference to the latter, the increasing temperatures that have been recorded on the Kenai
Peninsula (National Climate Data Center, 2003) which may influence the vegetation growing
period, as well as the movements of the caribou.
3
METHODS
Caribou Wintering Habitat Determination
The caribou winter-use areas were determined by radio-telemetry locations and visual
caribou sightings. Personnel from the KNWR, ADF&G, and Chugach National Forest collected
the movement data. In addition to movement information, observation on fecal pellets and
vegetation damage provided supplementary determinations of caribou-use areas. A categorical
herbivory index was developed using this information. A second herbivory index was generated
from the movement locations in a program called Statistical Ecology Analysis System (J. Carey
1989, pers. comm.). This program uses harmonic means of animal activity areas (Dixon &
Chapman, 1980) to create isopleths of “intensity of used surfaces”. This information was used to
both determine relative use of various sites and aid in determining appropriate caribou-use
sampling sites.
Vegetation Sampling
During the summers of 1988 and 1989 permanent macroplots (100 m2) were established
and sampled using 20 quadrats (0.25 m2) within (Fig. 3). Field sites included: 1) wintering areas
utilized by the second caribou introduction (1985-86); 2) wintering areas utilized by the initial
caribou introduction (1965-1966); and 3) four areas with similar general environmental indices
as the caribou winter used areas, without caribou activity. The caribou winter-use sites and the
control sites were as close as possible, with the average distances ranging from 16.5 km to 64.7
km. Vegetation was sampled during the summer because the snowfall precluded the primary
interest in the study, namely acquisition of vegetation community data. While some information
was lost, like vegetation conditions before caribou introductions and actual winter condition of
the vegetation, these deficiencies were unavoidable.
Macroplots were placed along transects through each study area. A systematic sampling
design (Braun-Blanquet, 1932; Greg-Smith, 1964; H.C. Hanson, 1950) was utilized to make
relocation and re-sampling possible. Fig. 4 and Table 1 list the caribou wintering areas of the
second introduction and locations of the vegetation sampling areas. There were 142-macroplots
in seven different sampling areas, for a total of 2840 quadrates and a total vegetation sampling
area of 710 m2. The proportion of sites sampled are 43% in the wintering areas used by the
second caribou introduction (Killey River and Fox River Herds), 42% in comparable areas
without caribou, and 15% in areas utilized by the initial caribou introduction (Kenai Mountains
4
Herd) in the winter. At the time of the initial caribou range study (1988-89), the Twin Lakes
area was not used by caribou. The 10-year revisit to a portion of the ranges included a
reassessment of a total of 25 macroplots from the following sampling areas (# macroplots):
Killey River Herd (14), Fox River Herd (8) and Mystery Hills (3) comparable area without
presence of caribou. Note, these three macroplots visited in the Mystery Hills comparable area
were originally sampled in 1989, therefore the revisit to these areas involved 9 years.
Information recorded included vegetation cover estimates (to the nearest 5%), vegetation
heights, lichen biomass samples, herbivory evidence, physical environmental parameters (slope,
aspect, elevation), and other groundcover values (exposed soil, rock, and dead vegetation).
Evidence of herbivory was visually documented by 1) number of fecal pellets from caribou and
other herbivores, 2) vegetation damage (vascular plant stripping and displacement of the lichen
mat or “cratering”), and 3) other evidence of animal activity (e.g., trails, holes).
In the initial sampling period, a sample of lichens in the four 0.25 m2 corner quadrants of
a macroplot were collected in paper bags and the living portions were oven-dried (typically 60
hours), by species, until a constant weight was achieved at 37 C. Regression equations were then
calculated to estimate biomass from cover values, and reduce lichen collecting. Macroplots that
had quadrats with lichens previously harvested were not included in the determination of
vegetation mean cover values in the 10-year revisit.
Snow Cover Information
Snow cover information (snow depth and snow-water equivalent) was obtained from the
snow cover monitoring stations of the Natural Resource Conservation Service (NRCS) National
Water and Climate Center (Clagett, 1990). The closest snow monitoring stations to the wintering
ranges of the caribou populations are stations Middle Fork Bradley (59.76º N., - 150.76 º E.) for
the Fox River Herd and Resurrection Pass (60.68º N., - 149.75º E.) for the Kenai Mountains
Herd. For the winter of 1988-89, winter range photos were taken by 60-30 North Aviation
Services (Nichols 1989, pers. comm.). Previous research has determined that the value at
which snow density may limit caribou from acquiring forage is estimated at density > 32%
(Pruitt, 1959).
5
Vegetation Analysis
In this assessment, vegetation quantities, heights, biomass, use and other obvious patterns
among sampling areas, are compared. In a M.S. research project performed by the author,
several multivariate techniques were used to detect other patterns and gradients in the vegetation
information obtained from the 1988-89 field season (Paez, 1991).
The assessment of trend information for a subset of 25 macroplots was obtained in July
1998, ten years post the initial study. These results, referenced in the paper as 10-year trend
study, yielded information concerning the differences in vegetation quantity, structure, and
herbivory evidence compared to the initial assessment of the ranges.
RESULTS
Caribou Population Ranges
By the time of the initial range survey (1988-89), the second caribou introduction (1985-
86) utilized two different wintering areas, the southern benchlands of Killey River (55 km2) and
Fox River (42 km2) (Fig. 4). In the winter prior to vegetation sampling, 1987-88, there were 70
caribou for the Killey River population and 22 in Fox River population (Bailey, 1988). The
average winter densities (i.e., # wintering caribou/area of wintering range) of caribou for these
entire areas were 1.27 caribou/km2 and 0.52 caribou/km2, respectively. The initial caribou
introduction (1965-66) utilized the habitats, by Big Indian Creek in the northern portion of the
Kenai Peninsula (Kenai Mountains). This amount of caribou in this herd consisted of 243
(Bailey, 1990) to 280 (Spraker, 1992) in the winter prior to vegetation sampling, 1988-1989. The
total winter range of this population was estimated at 520 km2 (Fig. 4). The average winter
density of this population was 0.47 km2. These caribou density figures are averages and
different parts of the ranges had different concentrations of caribou.
The potential winter-use areas without caribou were not devoid of herbivore evidence.
The principle herbivore in these areas was the Dall Sheep (Ovis dalli dalli). Suitable foraging
sites not used by either of the large herbivores, caribou or Dall Sheep, were few. A gradient of
herbivore “evidence” (e.g., field fecal pellet and vegetation-use evidence) was observed from the
least impacted areas, Mystery Hills and Russian Mountains, at one end to Kenai Mountains at the
other. In the areas used by the initial caribou introduction (Kenai Mountains), areas with the
6
entire vegetation mat was denuded with open patches and feeding craters was evident.
By the year 2001, the Killey River herd has increased substantially in size from the 1985-
86 reintroductions to its peak in of 710 (Ernst, et. al. 2007 in-prep); however, in December 2001
or January 2002, an avalanche killed 143 individuals (23 Males, 103 females, 9 calves, and 8
unidentified). The Fox River group had grown from 16 animals in 1986 to 96 in 1997 (Ernst, et.
al. 2007 in-prep); However by 2004, this population had declined to 25 in 2004. The Kenai
Mountain Herd grew from 15 introduced animals in 1965 to approx 450 animals at its peak in
1996, and since then the population has appeared to decline slightly (Ernst, et. al. 2007 in-prep).
The ranges of these caribou populations through 2005 (Ernst, et. al. 2007 in-prep.) are
represented in Figs. 5-7, with the ranges of the Killey River herd, in the 1990s and 2000s, were
approx 550.30 and 884.12 km2 respectively. Five collared caribou from the Killey River herd
moved to nunataks within the Harding Icefield to calve in the summers of 2000-2003, and,
subsequently, in the 2000s the estimate of the summer range was 749.24 km2 at 0.46
caribou/km2, which was larger than the winter range (554.89 km2 at 0.63 caribou/km2). The Fox
River herd also appeared to increase their range from approx 104.05 km2 (1990s) to 151.25 km2
(2000s); The Fox River herd had the smallest seasonal ranges of the four herds on the Peninsula
(summer, 118.27 km2 at 0.24 caribou/km2; winter, 95.97 km2 at 0.29 caribou/km2). The Kenai
Mountains herd area increased from approx 321.47 km2 in the 1990s to 710.79 km2 in the 2000s.
The summer and winter ranges from data in the 2000s were 626.48 (0.52 caribou/km2, density)
and 508.78 (0.64 caribou/km2) km2, respectively.
Vegetation Composition and Diversity
A total of 24 species of lichens, 39 species of vascular plants, brophytes, and fungus were
recorded (Table 2, Fig. 8). In all seven sampling areas (Table 3), the most prevalent lichen
species were Stereocaulon alpinum, Cladina rangiferina, Cladina mitis, and Cladina stellaris.
The predominant vascular plants were Empetrum nigrum, Diapensia lapponica, Dryas
octopetala, and Vaccinium caespitosum. Four groups of lichen species were not distinguished in
the earlier field season; thus, these were grouped for comparative analysis (Table 4). Concerning
caribou forage species, Cladina rangiferina and Cladina mitis, labelled as “Cladina group”, were
the most important of these combinations.
In reference to the characteristics of the vegetation in areas exposed to varying degrees of
7
caribou herbivory pressure, as the grazing pressure increased, the preferred lichen species
became less dominant with vascular plants, such as Dryas octopetala, Empetrum nigrum,
Diapensia lapponica and Vaccinium caespitosum becoming the dominant species based on mean
cover values. A similar relationship was found as in the study by Swanson & Barker (1992),
which indicated that the recovery of the lichen community is further complicated by competition
with the vascular-plant community. This trend of reduced lichen cover and increased vascular
plant cover was also seen by Henry and Gunn (1991), Klein (1987), and Helle and Aspi (1983).
Assuming interspecific competition occurring between the vegetation species within the
community, increases in these parameters may be due to reduction of the competitive abilities of
plants by herbivory, and a consequent reduced tendency towards dominance. This gradient
coincides with the relationship represented by the herbivory sign information. The amount of
herbivory sign in the 10-year revisit increased with the inclusion of feeding craters (Figs. 9-10),
which were previously only seen primarily in the Kenai Mountain Herd winter use areas.
In the 10-year trends study, the 14 macroplots visited from the Killey River Herd areas
yielded a decrease in the average lichen cover values for 9 of the 19 lichens recorded (Fig. 11),
most importantly in the preferred Cladina group (C. mitis & C. rangiferina) lichen species. The
eight macroplots within the Fox River Herd 10-year trends study yielded decreases in the
average lichen cover values for five of the 19 lichens recorded (Fig. 12). The differences in
mean cover values for the three macroplots from the Mystery Hills comparable habitats without
caribou were minor (Fig. 13). Large increases occurred in the White Sterile crust lichens
(Ochroleuca spp.) for the Killey River & Fox River caribou use areas (Figs. 14-15).
Ochroleuca spp. has been associated with disturbance, possibly related to abiotic factors such as
desiccation (wind stress) and biotic factors, such as herbivory. The Fox River Herd areas were
noticeably windy areas. The Mystery Hills comparable habitat did not have any cover value for
Ochroleuca spp. in 1989 and small amounts were present in 1998 (Fig. 16). This area is not
along exhibiting the high herbivory or extreme wind pressure, but does have some possible
disturbance from foot traffic, with a trail nearby.
The composition of the vascular plants exhibited similar changes as in the initial study,
with a pronounced increase in vascular plant cover amounts in the caribou-use areas (Figs. 17-
18). In the Fox River Herd caribou-winter use area, the dominant species that exhibited
8
increases included Dryas octopetalia, Diapensia lapponica and Empetrum nigrum. The vascular
plants within the Killey River area exhibited similar increases, particularly in Dryas octopetalia,
Diapensia lapponica and Emptrum nigrum. These changes in both the lichen and vascular plant
species composition and cover values were not that evident in the 10-year study of the Mystery
Hill Comparable Caribou Habitat Areas (Fig. 19).
Vegetation Heights
The mean heights of vascular plants were ≤5 cm. for all macroplots in this windswept
alpine tundra. Lichen live podetia heights differed most between the least impacted non-caribou
use sites, Mystery Hills and Russian Mountains, with the rest of the areas. For the 10-year
trends study, the differences in live lichen podetia heights from the Killey River, Fox River and
Mystery Hills comparable caribou use areas mirrored the relationship evident in the mean cover
values. The Killey River and Fox River caribou winter-use areas exhibited pronounced
decreases in preferred lichen heights (Figs. 20-21), while the Mystery Hills comparable caribou
habitat lichen live podentia lichen heights exhibited minor differences (Fig. 22).
Lichen Biomass Information
The regression of biomass against cover shows that biomass can be estimated well from
its cover data. Half of the species analyzed had high correlation, with r2 > 0.80 (p < .01) (Table
5). This information has potential for being extrapolated for estimating the amount of potential
lichen biomass available within the caribou ranges. Such an extrapolation can be used for
estimating carrying capacities. However, as stated earlier, with the free-ranging capability of the
caribou, possibly a greater limitation would be the availability of quality forage, not necessarily
quantity.
Abiotic Elements
The general environmental variables of slope, aspect, and elevation between caribou
winter-use areas and comparable areas without caribou were similar in all sampled areas
(Table 6). In addition to these variables, the bedrock type that occurs in the caribou winter-use
areas and control areas is the Graywacke-Argillite and other consolidated rocks formations
(Karlstrom, 1964). Multivariate techniques utilized in (Paez, 1991) to provide quantitative
environmental values as variables (excluding slope and aspect which showed little variance
between groups) to predict sampling area membership, 98% of the 82 cases (macroplots) from
9
the caribou-use group were predicted correctly; and 92% of the 60 cases from the control areas
were predicted correctly. There was virtually no correlation of any environmental variable (all r
< .16) along this axis. Therefore, confidence occurred in that all caribou and control areas were
indeed similar in terms of the physical environment.
Snow Cover Information
According to information from NRCS stations, the snow density values of 32% and
greater were present in the later winter months of 1988-89, indicating that snow conditions were
possibly limiting the caribou from acquiring forage. However, this is a general estimate since it
does not provide information concerning possible “rain crusts” which could prevent foraging at
lesser snow depths (Swanson 1989, pers. comm.). In the winter prior to sampling the
reintroduced caribou-use areas, the snow characteristics at the Middle Fork Bradley station
indicated density percentages at or greater than the value of 30%.
In the winter of 1988-89, information for the longer-established caribou population from
the NRCS Resurrection Pass station was not complete; however, data from a 25-year average of
that station indicated densities were greater than 30% in the late winter months. Winter
photographic survey flights indicated complete snow cover with minimal exposed areas (Nichols
1989, pers. comm.). From 1961-1985, the northern, mountainous region averaged approx 270
cm of precipitation at 570 m while the southern region averaged 75 cm at 360 m (Soil
Conservation Service 1988) although levels of precipitation can vary greatly from year to year.
DISCUSSION
The caribou pressure on the vegetation community may create or modify the spatial
heterogeneity within the system. There are many components to which the vegetation responds,
and only a few have been studied here. It is clear that the caribou do have a profound effect on
the vegetation. Some changes, such as feeding craters in the areas used by caribou populations,
are obvious; but others such as interspecific competition among plant communities and
interaction with environmental elements, may be quite subtle.
Through these analyses, several similarities resulted which may allow the following
suppositions. Compared to vascular plants, lichen species have provided more variance in the
data set. This indicates the importance of lichens in the structure and pattern of these tundra
10
communities, which are undergoing varied herbivory. In addition, when vegetation and
environment information are analyzed together, the vegetation provides more variance in the
data set. This suggests the areas chosen for this comparative study are comparable in their
environments to the extent they were measured.
Other information for this tundra/caribou interaction lies in the index related to caribou
densities associated with the ranges. Combining data from the densities of caribou winter-
activity locations with associated macroplot information for these areas, a comparison on the
effects of this presence can be made. In Figure 8, Mean Lichen % Cover Values per Sampling
Area – Initial 1988-1989 Sampling Period, the mean cover amounts of the preferred lichen
species, Cladina spp., and Cladina stellaris, between the assemblages of caribou-use areas and
the least disturbed comparable areas without caribou, Mystery Hills and Russian Mountains, are
the most impressive. Reductions in live lichen podetia heights between these areas (Figs. 19-20)
coincide with this relationship. There is also a reduced lichen cover and increased vascular plant
cover (Figs. 11-12, 16-17), a trend also seen by Henry and Gunn (1991), Klein (1987), and Helle
and Aspi (1983). The increase in the White Crust lichen Ochroleuca spp. (Figs. 14-15) in the
Killey River and Fox River caribou winter use areas is another indicator of the harsh
environment present there, both in herbivory and desiccation for the vegetation. The Fox River
Area is especially prevalent to extreme wind conditions.
As stated in the beginning of the paper, the caribou environmental needs of escape or
finding relief from flying insects in the summer and acquiring food through deep snow in the
winter can be major obstacles to their viability. The free-ranging capability of the caribou,
affords them the possibly of seeking better habitats with less flying insects and better quality
forage. Their wide-ranging movements on the Kenai Peninsula, particularly the Killey River
Herd, have shown this capability. However, there are compounding factors on the Kenai
Peninsula, such as the insular nature of the Peninsula, and the hazards present through glaciers
and other difficult travel corridors, which may reduce their viability. In addition, the
surmounting changes expressed by the changing climate may compound these limitations.
Overall, the caribou and its habitat may stay viable on the Kenai Peninsula if the innate ability of
the caribou to migrate is not limited. This study has documented some of the vegetation issues
associated with caribou and their habitat, and provides comparative studies based upon on these
findings.
11
MANAGEMENT RECOMMENDATIONS
Detailed assessments of caribou ranges, which include the acquisition of large sample
sizes of field-derived information, are impractical for most management agencies. Unlike the
reindeer populations, which are herded to various wintering areas, the movements of caribou are
uncontrolled. With the insular characteristics of the Kenai Peninsula, the winter range is a
serious concern since introduced caribou population can undergo nearly exponential growth
while their food supply depends largely on slow growing lichens. In addition, some of the
winter and summer ranges of these caribou herds are not distinct.
A feasible approach may be to utilize a methodology, which affords the possibility of
forecasting what type of vegetation community is envisioned with a specific grazing pressure.
This type of method which relates the effects of grazing pressure to the “ecological status or
condition” has been utilized for reindeer management (Swanson et. al., 1983, 1992; Shiftlet,
1973; Dyksterhuis, 1958). This technique, briefly described, recognizes the concept of “climax
communities” implies stability, which is questioned by some, but can serve as a guide to what
type of community could be expected, under certain environmental conditions in the near future.
Other types of rangeland assessments can be performed utilizing remotely sensed imagery for
determining ecological site descriptions and rangeland evaluations (Maynard, et. al. 2007).
It has been demonstrated in this study and confirmed by other studies the changes that
occur to the lichen and vascular plant community structure with prolonged grazing. This
expectation can provide information concerning the limits of carrying capacity of rangelands for
herbivorous predators.
12
LITERATURE CITED
ANDREEV, V.N. (1954). Growth of forage lichens and methods for their regulation. Trudy
Botahicheskogo institura im.V.L. Komarova Akademiia Nauk SSSR, Series
III.Geobotanika,9:11-74.
BAILEY, T. N. 1985 .Environmental Assessment for the Reintroduction, Monitoring, and
Management of Caribou (Rangifer tarandus) in the Central and Southern Regions of the
Kenai National Wildlife Refuge. Public Law 94-487 Section 303(4) (B) (i).
1990. Caribou reintroduction project on the Kenai Peninsula, 1985 and 1986 - Final
Report.
BERGERUD, A.T. 1978. Caribou. pgs. 83-101.in Schmidt, John and Douglas L. Gilbert, (eds.)
Big Game of North America, Ecology and Management. Wildlife Management Institute.
Stakpole Books, Harrisburg, PN.
BRAUN-BLANQUET, J. 1932. Plant sociology, the study of plant communities. (Transl. by
G.D. Fuller and H.S. Conrad). Transl. of 1st ed. of Pflanzensoziologie (1928). McGraw-
Hill, New York and London.
BURNS, O. E. AND D.E. MCKNIGHT. 1973. Game Transplants in Alaska. Wildlife Tech. Bull.
No. 4. Alaska Dept. of Fish and Game, Juneau. 57pp.
CARY, J.R. 1989. (pers. comm.). Department of Wildlife Ecology, 1630 Linden Drive, Room
226, University of Wisconsin, Madison, WI 53706-1598 USA
CLAGETT, G.P. 1990. Alaska Cooperative Snow Survey Data of Federal-State-Private Snow
Surveys.Issued as: Alaska Annual Data Summary Water Year 1990.United States.
Department of Agriculture, Soil Conservation Service, Anchorage, Alaska. 2Opp.
DAVIS, J.L. AND A.W. FRANZMANN. 1979. Fire-Moose-Canibou Interrelationships. Pages
13
80-118 in Proceedings of the North American Moose Conference and Workshop.No.15.
March 1979. Soldotna-Kenai , Alaska.
DIXON, K.R. AND J.A. CHAPMAN. 1980. Harmonic mean measure of animal activity areas.
Ecology. 61(5):1040-1044.
DYKSTERHUIS, E.J.1958.Range conservation as based on sites and conditions classes. Journal
of Soil Water Conservation 13 (1958), pp. 151–155
EGAN, R.S. 1987.A fifth checklist of the lichen-forming, lichenicolous and allied fungi of the
Continental United States and Canada. The Bryologist 90(2):77-173.
ERNST, R.D, D.D. GUSTINE, J.M. MORTON, T.N. BAILEY, T.H. SPRAKER, W.L.
LARNED AND E.E. BANGS 2007. Reintroduction of Caribou to the Kenai Peninsula,
Alaska. (in-prep).
GREG-SMITH, P. 1964. Quantitative plant ecology.2nd ed. Butterworths, London. 256pp.
HANSON, H.C. 1950. Ecology of the Grassland. The Bot.Rev. 16(6) :283-260.
HELLE, T. AND J. ASPI. 1983. Effects of winter grazing by reindeer on Vegetation. Oikos
40:337-343.
HENRY, G. H. R. AND A. GUNN. 1991 .Recovery of vegetation after overgrazing by caribou
in arctic Canada. Arctic.44(1):38-42.
HULTÉN, E.H. 1968. Flora of Alaska and neighboring ternitonies. A manuel of the vascular
plants. Stanford Univ. Press. Stanford, CA.1, 1008pp.
KANLSTROM, T.N.V. 1964.Quaternary Geology of the Kenai Lowland and Glacial History of
the Cook Inlet Region, Alaska. Geological Survey Professional Paper-
443.U.S.Govt.Printing Office, Washington.
14
KLEIN, D. R. 1987. Vegetation recovery patterns following overgrazing by reindeer on St.
Matthews Island. J. Range. Mgt. 40:336-338.
KLEIN, D.R. AND P.C. LENT. 1988. Tundra vegetation as a rangeland resource. In Tueller,
P.T. (ed). ,Vegetation Science Applications for Rangeland Analysis and
Management.Kluwer Academic Publishers. Boston, CT. London, England.
MAYNARD,C.L., R.L.LAWRENCE, G.A. NIELSEN AND G.DECKER.2007.Ecological site
descriptions and remotely sensed imagery as a tool for rangeland evaluation.
Can.J.Remote Sensing, Vol.33,No.2,pp.109-115.
MILLER, F.L. 1982.Caribou (Rangifer tarandus).Pages 923-959 in J.A.Chapman and
G.A.Feldhamer (eds).Wild Mammals of North America.John Hopkins
Univ.Press.Baltimore,Maryland.
NATIONAL CLIMATE DATA CENTER. 2003. Kenai municipal airport weather station data.
[online]. Available from: http://www.ncdc.noaa.gov/oa/ncdc.html
NICHOLS, L. 1978. Dall Sheep. pgs.173-189. in Schmidt, John and Douglas L. Gilbert, (eds.)
Big Game of North America, Ecology and Management. Wildlife Management Institute.
Stakpole Books, Harrisburg, PN.
1989.(pers. comm.). Alaska Department of Fish & Game, Cooper Landing, Alaska.
NOWACKI, G., M. SHEPHARD, P. KROSSE, W. PAWUK, G. FISHER, J. BAICHTAL, D.
BREW, E.. KISSINGER, AND T. BROCK. 2001. Ecological Subsections of southeast
Alaska and neighboring areas of Canada. Draft Report U.S. Forest Service, Tongass
National Forest, Juneau, Alaska.
15
PAEZ, C.E.1991.Alpine vegetation of areas utilized by introduced populations of caribou
(Rangifer tarandus) on the Kenai Peninsula, Alaska. M.S. Thesis, University of
Wisconsin-Madison.261pp.
PALMER, L.J. 1938. Management of moose herd on the Kenai Peninsula. Res. Proj. Rept.
March, April, May 1938. Unpublished manuscript. Kenai National Wildlife Refuge Files,
Soldotna.
PORTER, R.P. 1893. Report on populations and resources of Alaska at the Eleventh
Census:1890.U.S. Dept. of Interior, Census Office. 282pp.
PRUITT, W.O. ,JR. 1959. Snow as a factor in the winter-ecology of the barren-ground caribou.
Arctic. (12): 158-179.
SCHIEFNER, A. 1874. Leopold Radloff’s Worterbuck den Kinai Sprache. Memories de
L’Academie Impeniale des Sciences de St.Petersbourg. Vol.VIIe Senies.Tone XXI,No.8.
SETON-KARR, H.W. 1887. Shores and alps of Alaska. A.C. McClurg and Company.Chicago,
Illinois. 248pp.
SPRAKER, T. 1992. Reintroduction of caribou to the central and southern Kenai, Peninsula,
1985-86. Alaska Department of Fish and Game, Juneau, Alaska.Wildlife Technical
Bulletin No. 9.
SWANSON, J. D.; BARKER, M. H. W. 1992. Assessment of Alaska reindeer populations and
range conditions. Rangifer. 12(1): 22-43.
SWANSON, J.D., AND M.P. KINNEY. 1983. Reindeer range vegetation inventory procedures.
Acta Zoológica Fennica. 175:39-41.
16
Figures & Tables:
Fig. 1. Kenai Peninsula in Southcentral Alaska
Fig. 2. Kenai Peninsula and the location of Federal Lands – Kenai National Wildlife Refuge, Chugach National Forest and Kenai Fjords National Park
17
Fig. 3. Macroplot (100 m2) with 20 – ¼ m2 quadrats
Caribou-Use Areas (# Macroplots) Comparable Areas without Caribou (# Macroplots)
1 – Killey River (41) 3 – Mystery Hills (13) 2 – Fox River (20) 4 – Russian Mountains (14) 7 – Kenai Mountains (21) 5 – Twin Lakes (20) 6 – Cottonwood Creek (13)
Table 1. Macroplot (100 m2) Sampling Areas
Fig. 4. Enlargened view of the Kenai Peninsula with Caribou Winter Ranges Outlines & Macroplot Locations.
18
Fig. 5. Caribou Ranges (all herds) on the Kenai Peninsula (2005).
Fig. 6. Second Caribou Introduction (1985-86) Ranges on the Kenai Peninsula (2005).
19
Fig. 7. First Caribou Introduction (1965-66) Kenai Mountains Herd Range on the Kenai Peninsula 2005. Table 2. Species Composition for the Caribou Winter Range Analysis Project
Scientific Name Scientific Name Abbreviation Abbreviation Alectorica divergens Alec. div. 1 31 Brophyta spp. moss
2 Bryocaulon divergens Bry. div. 32 Pedicularis spp. Ped. spp. 3 Cetraria cucullata Cet. cuc. 33 Cyperaceae spp. sedge 4 Cetraria ericetorum Cet. eri. 34 Gramineae spp. grass 5 Cetraria islandica Cet. isl. 35 Loiseleuria procumbens Lois. p. 6 Cetraria nivalis Cet. niv. 36 Saxifraga bronchialis Sax. br. 7 Cladina mitis Cla. mit. 37 Silene acaulis Sil. ac. 8 Cladina rangiferina Cla. ran. 38 Arnica frigidia Arn. fr. 9 Cladina stellaris Cla. ste. 39 Anemone narcissiflora Anem. n. 10 Cladonia gracilis Cla.gr 40 Astragalus umbellatus Ast. um. 11 Cladonia amaurocraea Cla.am 41 Oxytropis nigrescens Oxy. ni. 12 Cladonia unicialis Cla.un 42 Oxytropis campestris Oxy.ca. 13 Dacylina arctica Dac.ar 43 Diapensia lapponica Dia. la. 14 Lobaria linita Lob.li 44 Arctostaphylos alpina Arc. al. 15 Umbilicaria proboscidea Umb.pr 45 Pedicularis capitata Ped. ca. 16 Pseudephebe pubescens Pse.pu 46 Pedicularis lanata Ped. la. 17 Sphaerophorus globosus Sph.gl 47 Pedicularis oederi Ped. oe 18 Stereocaulon alpinum Ste.al 48 Lycopodium spp. Lyco. 19 Thamnolina vermicularis/ subliformis group Tha.ve 49 Ledum decumbens Led. de. 20 Ochroleuca spp. (white crust lichen) Ochro. spp. 50 Minuartia arctica Min. ar. 21 Salix arctica Sal. ar. 51 Gentiana glauca Gen. gl. 22 Salix reticulata Sal. re. 52 Geum rossii Geum r. 23 Salix ovalifolia Sal. ov. 53 Lloydia serotina Lloy. s. 24 Dryas octopetalia Dry.oc. 54 Primula cuneifolia Pri. cu. 25 Betula nana Bet. na. 55 Artemisia campestris Art. ca 26 Betula glandulosa Bet. gl. 56 Polygonum viviparum Poly. v. 27 Betula nana X glandulosa hybrid Bet. hy. 57 Tofieldia coccinea Tof. co. 28 Vaccinium caespitosum Vac. ca. 58 Antennaria monocephala Ant. mo. 29 Empetrum nigrum Emp. ni. 59 Spirea beauvardiana Spir. b. 30 Vaccinium vitis-idaea L. Vac. vi. 60 Campanula lasiocarpa Camp. l. 61 Fungi spp. Mushrm.
20
21
Table 3. Lichen Species % Cover Mean Values per Sampling Area²
Species¹ SKI TRU BIG MYS RUS TWI COT macroplots 41 20 21 13 14 20 13
Ale.och. 0.35 0.54 0.84 1.49 2.87 0.58 0.49 Bry.div. 0.58 0.19 2.03 2.04 1.89 0.26 0.35 Cet.cuc. 0.52 0.34 0.60 1.24 0.43 0.81 0.84 Cet.spp. 0.57 0.57 0.32 0.39 0.38 0.48 0.34 Cet.niv. 0.92 1.18 1.39 3.53 5.07 1.39 1.10 Cla.spp. 1.75 2.67 1.60 5.07 4.15 2.14 2.33 Cla.ste. 0.55 1.50 3.57 10.12 8.36 0.59 1.67 Cld.gra. 0.16 0.35 0.69 0.72 0.50 0.90 0.37 Cld.spp. 0.32 0.45 0.35 0.25 0.72 0.11 0.17 Dac.arc. 0.05 0.04 0.13 0.00 0.004 0.68 0.05 Lob.spp. 0.33 0.21 0.08 0.00 0.00 0.68 0.03 Pse.pub. 3.07 1.27 0.81 0.06 0.20 3.11 0.95 Sph.glo. 0.27 0.36 0.73 0.56 0.72 0.34 0.98 Ste.alp. 3.12 2.35 1.44 4.59 2.67 8.20 14.17 Tha.spp. 1.10 1.01 0.88 1.05 1.21 1.21 0.95
¹refer to tables 2 & 4 ² Initial 1988-1989 Sampling Period - Skilak Tustumena or Killey River Herd (SKI),Truuli Creek (TRU) or Fox River Herd, Big Indian or Kenai Mountain Herd (BIG),Mystery Hills (MYS),Russian Mountains (RUS),Twin Lakes (TWI),Cotton Hills (COT). Caribou winter use areas in bold. Table 4. Grouped Lichen Species
Scientific Name Abbreviation
1 Cetraria ericetorum & Cet. islandica Cet. gp. 2 Cladina mitis & Cl. rangiferina Cl. gp. 3 Cladonia amaurocraea & Cla. unicialis Cla. gp. 4 Lobaria linita & Umbilicaria proboscidea Lob. gp. 5 Thamnolina vermicularis & T. subliformis Th. gp.
Ale
.och
.
Bry
.div
.
Cet
.cuc
.
Cet
.spp
.
Cet
.niv
.
Cla
.spp
.
Cla
.ste
.
Cld
.gra
.
Cld
.spp
.
Dac
.arc
.
Lob.
spp.
Pse.
pub.
Sph.
glo.
Ste.
alp.
Tha.
spp.
SK
I (41
)TR
U (2
0) B
IG (2
1)M
YS (1
3)R
US
(14)
TWI (
20)
CO
T (1
3)
0
2
4
6
8
10
12
14
16
Mea
n %
Cov
er V
alue
s pe
r Sam
plin
g A
rea
Lichen Species
Sampling Area
Mean Lichen % Cover Values per Sampling Area
SKI (41) TRU (20)
BIG (21) MYS (13)
RUS (14) TWI (20)
COT (13)
Fig. 8. Mean Lichen % Cover Values per Sampling Area – Initial 1988-1989 Sampling Period. Skilak Tustumena (SKI) or Killey River Herd, Truuli Creek (TRU) or Fox River Herd, Big Indian (BIG) or Kenai Mountain Herd Mystery Hills (MYS), Russian Mountains (RUS), Twin Lakes (TWI),Cotton Hills (COT).
22
Killey River Herbivory Data expressed as Piles and Craters
0
5
10
15
20
25
K010 K012 K015 K017 K024 K025 K026 K027 K031 K033 K036 K037 K040 K041
Killey River Herd Macroplots
Num
ber
of P
iles
& C
rate
rs
1988 Piles Data1998 Piles Data1988 Crater Data1998 Crater Data
Fig. 9. Killey River Herd Caribou Piles & Cratering Trend Information
Fox River Herd Herbivory Information expressed as Piles and Craters
0
5
10
15
20
25
T042 T043 T046 T047 T048 T054 T055 T059
Fox River Herd Macroplots
Num
ber
of P
iles
& C
rate
rs
1988 Piles Data1998 Piles Data1988 Crater Data1998 Crater Data
Fig. 10. Fox River Herd Caribou Piles & Cratering Trend Information
23
Alec
.och
.Br
yoc.
div.
Cet
ra.c
u.C
et.g
p.C
etra
.niv
.
Cl.g
p.
Cla
d.st
ell.
Cla
d.gr
ac.
Cla
.gp.
Dac
t.arc
t.
Lob.
gp.
Psed
u.pu
.
Spha
e.gl
.
Ster
eo.a
l.
Tham
n.ve
.
19881998
0
0.5
1
1.5
2
2.5
3M
ean
% C
over
Val
ue
Lichen Species
Year
Killey River Herd Average Lichen Cover Values in 1988 & 1998 within 14 Macroplots
1988
1998
Fig. 11. Killey River Herd Average Lichen Cover Values Trend Information
Alec
.och
.Br
yoc.
div.
Cet
ra.c
u.C
et.g
p.C
etra
.niv
.
Cl.g
p.
Cla
d.st
ell.
Cla
d.gr
ac.
Cla
.gp.
Dac
t.arc
t.
Lob.
gp.
Psed
u.pu
.
Spha
e.gl
.
Ster
eo.a
l.
Tham
n.ve
.
1988
0
0.5
1
1.5
2
2.5
3
Mea
n %
Cov
er V
alue
Lichen Species
Year
Fox River Herd Average Lichen Cover Values in 1988 & 1998 within 8 Macroplots
19881998
Fig. 12. Fox River Herd Average Lichen Cover Values Trend Information
24
Ale
c.oc
h.
Bry
oc.d
iv.
Cet
ra.c
u.
Cet
.gp.
Cet
ra.n
iv.
Cl.g
p.
Cla
d.st
ell.
Cla
d.gr
ac.
Cla
.gp.
Dac
t.arc
t.
Lob.
gp.
Pse
du.p
u.
Sph
ae.g
l.
Ste
reo.
al.
Tham
n.ve
.
19891998
0
5
10
15
20
Mea
n %
Cov
er V
alue
Lichen Species
Year
Mystery Hills Comparable Caribou Habitat
19891998
Fig. 13. Mystery Hills Comparable Caribou Habitat Average Lichen Cover Values Trend Information.
0
5
10
15
20
25
Mea
n %
Cov
er
K01
0
K01
2
K01
5
K01
7
K02
4
K02
5
K02
6
K02
7
K03
1
K03
3
K03
6
K03
7
K04
0
K04
1
Killey River Herd Macroplots
White Crust Lichen Mean % Cover Values
19981988
Fig. 14. Killey River Herd White Crust Lichen (Ochroleuca spp.) trend information.
05
10152025303540
Mea
n %
Cov
er V
alue
T042
T043
T046
T047
T048
T054
T055
T059
Fox River Herd Macroplots
White Crust Lichen Mean % Cover Values
19981988
Fig. 15. Fox River Herd White Crust Lichen (Ochroleuca spp.) trend information.
25
0
2
4
Mea
n %
C
over
102 138 139
M ystery Hills Control Area M acroplots
White Crust Lichen Mean % Cover
19981989
Fig. 16. Mystery Hills Comparable Caribou Habitat White Crust Lichen (Ochroleuca spp.) trend information.
Dryas.oct. Empet.ni. Vacc. ca. Diap.lapp.Grami.sp.
1988
19980
2
4
6
8
10
12
14
Mea
n %
Cov
er V
alu
Vascular Plant Species
Year
Killey River Herd Dominant Vascular Plants in 1988 & 1998 within 14 Macroplots
19881998
Fig. 17. Killey River Herd Dominant Vascular Plants trend information.
26
Empe
t.ni.
Dry
as.o
ct.
Dia
p.la
pp.
Vacc
. ca.
Salix
arc
t.
Lois
e.pr
o.
19881998
0
2
4
6
8
10
12
14
Mea
n %
Cov
er V
alue
Vascular Plant Species
Year
Fox River Average Dominant Vascular Plant Cover Values in 1988 & 1998 within 8 Macroplots
19881998
Fig. 18. Fox River Herd Dominant Vascular Plants trend information.
Dryas.oct. Empet.ni. Diap.lapp. Ledu. de. Grami.sp.
198919980
2
4
6
8
10
12
Mea
n %
Cov
er
Vascular Plant Species
Year
Mystery Hills Average Dominant Vascular Plant Cover Values in 1989 & 1998 within 3 Macroplots
19891998
Fig. 19. Mystery Hill Comparable Caribou Habitat Dominant Vascular Plants trend information.
27
K010 K012 K015 K017 K024 K025 K026 K027 K031 K033 K036 K037 K040 K041
19881998
0
0.5
1
1.5
2
2.5
3
Hei
ght (
cm)
Killey River Herd Plots
Live Lichen Heights of Cladina spp. (C.rangiferina & C. mitis ) per Field Season
19881998
Fig. 20. Killey River Herd comparative Cladina spp. lichen live podetia heights.
T042T043
T046T047
T048T054
T055T059
1988
1998
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
Hei
ght (
cm)
Fox River Herd Plots
Live Lichen Heights of Cladina spp. (C.rangiferina & C. mitis ) per Field Season
19881998
Fig. 21. Fox River Herd comparative Cladina spp. lichen live podetia heights.
28
0
2
4
6ce
ntim
eter
s
102 138 139
19891998
Mystery Hills Control Area Macroplots
Cladina spp. (C. rangiferina & C. mitis ) Live Podetia Heights per Field Season
19891998
Fig. 22. Mystery Hill Comparative Caribou Habitat Lichen live podetia heights.
Table 5. Regression of Lichen Cover Values to Biomass
R2 Lichen Species n SE
Alectoria ochroleuca 32 1.736 0.865
Bryocaulon divergens 34 1.833 0.831
Cetraria cucullata 29 1.919 0.893
Cetraria spp2. 40 0.951 0.913
Cetraria nivalis 52 2.506 0.708
Cladina spp3. 65 10.03 0.649
Cladina stellaris 37 9.191 0.726
Cladonia gracilis 30 3.351 0.801
Cladonia spp4. 15 11.68 0.399
Sphaerophorus globosus 22 1.423 0.697
Stereocaulon alpinum 38 8.410 0.905
Thamnolia spp5. 39 1.027 0.736
2 Cetraria ericetorium & islandica 3 Cladina mitis & rangiferina 4 Cladonia amaurocraea & unicialis
295 Thamnolina vermicularis or subliformis
30
Table 6. Mean Slope, Aspect, & Elevation Information per Sampling Area Sampling Area1 Environmental Variables2
Slope Aspect Elevation Killey River Herd (2) 0 - 4 135 - 224 321 - 338 Fox River Herd (2) 0 - 4 45 - 134 339 - 356 Mystery Hills (P) 0 - 4 45 - 134 268 - 285 Russian Mts. (P) 0 - 4 135 - 224 303 - 320 Twin Lakes (P) 0 - 4 45 - 134 321 - 338 Cottonwood Ck. (P) 0 - 4 135 - 224 303 - 320 Kenai Mountains Herd (1) 4 - 8 45 - 134 285 - 303 1 Area Index: 2 = Second Caribou Introduction Winter-Use Area 1 = First Caribou Introduction Winter-Use Area P = Potential Caribou Winter-Use Area 2 Variables Index: Slope = in degrees, Aspect = in compass bearings Elevation = in meters